I think this is the deprecated to do it, now that they have docker connect, but it works, so I'll keep the notes.
My goal was to link a container that I'd set up to run a Jupyter Notebook server to a Mongo DB server. I'll leave out the installation notes and just assume that there's a docker image named mongo for MongoDB and one named jupyter for my Jupyter server.
First I'll run MongoDB. MongoDB is going to use /data/db to store its data-files so I'm going to mount my data directory there.
Next I'll run the Jupyter container, using the --link option to point it to the mongo container. The jupyter notebook is running on port 8888 and looking for notebooks in the /notebooks directory so I'll mount my current working director there.
At this point, opening a browser at http://localhost:8888 should open up the jupyter-server's home.